The elites built large doomsday bunkers at higher elevations, like the Cheyenne Mountain Complex, an impenetrable doomsday city built at 9,565 feet (2,916 meters), with the hope that the 2-mile-high waves would not reach it.This is also the reason why so many doomsday bunkers were built high in the Alps.China also has a massive complex built at a higher elevation that could house more than 1 million members of its elite.